A conveyor is frequently used to move signatures between a number of operating stations. Signatures typically comprise one or more pages which are formed into newspapers, magazines, pamphlets, or the like. The operating stations, which are supplied with signatures by the conveyor, perform selected operations upon those signatures. These operations may include such functions as collating, trimming, binding, and the like.
One known conveyor for conveying signatures to various operating stations includes a gathering chain having a plurality of inverted V-shaped gathering chain links suitably attached to a chain which is propelled by one or more motor driven sprockets. Each of the inverted V-shaped gathering chain links has a pair of depending legs joined at an apex. A pair of openings, one in each of the depending legs, are aligned to receive a gathering chain pin. Gathering chain pins are inserted through the openings in selected ones of the gathering chain links. Signatures are dropped onto the gathering chain so that the backbones of the signatures ride on the apexes of the inverted V-shaped gathering chain links of the gathering chain. The signatures are gathered by corresponding gathering chain pins such that the signatures are then driven along with the gathering chain by their corresponding gathering chain pins.
One existing gathering chain pin has a generally arcuate body. The generally arcuate body has an inner surface formed by an inner radius of the generally arcuate body, and an outer surface formed by an outer radius of the generally arcuate body. The outer surface of the generally arcuate body has a ridge so that, as the gathering chain pin is inserted through the openings of a gathering chain link, the ridge engages with one of the depending legs of the gathering chain link to thereby prevent the gathering chain pin from being pushed all the way through the openings of the gathering chain link. Once inserted, the ends of the generally arcuate gathering chain pin point in a generally upward direction so as to engage a signature and thereby facilitate both the gathering of the signature and the movement of the signature by the gathering chain.
A gathering chain pin of this design frequently becomes at least partially dislodged from its gathering chain. If the gathering chain pin becomes sufficiently dislodged and slides far enough out of position, it can strike adjacent apparatus with enough force to break. A broken gathering chain pin may fail to properly gather signatures and/or may fail to properly move signatures from operating station to operating station. Accordingly, operating stations supplied with signatures by a gathering chain conveyor having one or more broken gathering chain pins may fail to properly operate on the signatures.